SPECIES_MASS (.cell)

Keyword type

Block

Description

This data block contains mass of each atomic species. It has the following format:

%BLOCK SPECIES_MASS
[units]
	CCC1/I1 	R1
	CCC2/I2 	R2
	.
	.
	.
%ENDBLOCK SPECIES_MASS

The first entry on a line is the symbol or atomic number of the species. This must correspond with the species symbol or atomic number of the species in the POSITIONS_FRAC or POSITIONS_ABS block. The second entry on each line is the mass of that species.

Not all of the species present in the system have to appear in the SPECIES_MASS block. Any that are not present will be assigned the default mass for that species. However, if the symbol specified for a species is not a standard symbol in the periodic table, the mass of the species must be specified.

[units] specifies the units in which the masses are defined. If no units are given, the default of atomic mass units is used.

Example

%BLOCK SPECIES_MASS
       O     15.9989995956
      Al     26.9820003510
      Ti     47.9000015259
      Cs    132.9049987793
%ENDBLOCK SPECIES_MASS
See Also:

POSITIONS_FRAC
POSITIONS_ABS
CASTEP keyword glossary
CASTEP cell keywords and data blocks